The present invention relates to an elevating apparatus mounted on a mobile vehicle such as a truck or a crawler-type vehicle for elevating workers and/or materials at construction sites, for example.
There have heretofore been known elevating apparatus for lifting and lowering workers, materials and/or tools at various places for construction, painting, repair or other types of work. One prior type of elevating apparatus includes pairs of arms pivotably interconnected at their middle portions to provide a foldable or collapsable X-shaped or pantograph assembly.
It has been customary practice to provide an elevating mechanism capable of reaching a higher location by coupling a plurality of such X-shaped or pantograph assemblies as a vertically extensible structure. The interconnected elevating mechanism, however, is complicated in construction and unstable in operation. It is also disadvantageous in that the platform cannot be lowered to a level near a ground surface and tends to be wobbly at a lifted level.